The attack took place at Altnagelvin Hospital.
The Western Trust has sought to assure the public that oxygen supplies at Altnagelvin Hospital are secure.
However, the Derry hospital added that mitigation measures are in place in the event that oxygen levels are depleted further including the provision of portable canisters.
It comes after Sean Gibson, head of estate management at the Western Health Trust, warned that if demand for oxygen at the hospital continues to grow, due to increasing numbers of Covid patients, then oxygen may have to be rationed.
If the situation becomes unmanageable at the Derry hospital patients will be sent to the Nightingale Hospital in Belfast.
A spokesperson for the Trust stated: "The Western Health and Social Care Trust would like to reassure patients that oxygen supplies to Altnagelvin are secure. Indeed, the supply at present has a green status.
"Our Head of Estates Management has rightly highlighted the recent scale of demand for oxygen given Covid-19 infection and hospital admission levels.
"He also warned of the escalating pressures should the exponential growth in cases continue unchecked. As highlighted yesterday, that growth has been significantly checked in the Derry and Strabane council area.
"As part of its surge planning, the Northern Ireland Health Service has mitigation measures in place should oxygen supplies to individual hospitals become an issue. These include the provision of additional portable canister supplies and, if required, the centralisation of care in the regional Nightingale hospital at the City Hospital.
"Vital work is ongoing across the Health and Social Care system to ensure services are not overwhelmed by the present Covid-19 surge.
"The public has a vital and central role to play in that regard – by doing everything they can to stop the virus spreading."
If you have a story or want to send a photo or video to us please contact the Derry Now editorial team on 028 7129 6600 for Derry City stories Or 028 7774 3970 for County Derry stories. Or you can email email@example.com or firstname.lastname@example.org at any time.
Subscribe or register today to discover more from Derrynow.com
Buy the e-paper of the Derry News and the County Derry Post here for instant access to Derry's premier news titles.
Keep up with the latest news from Derry with our daily newsletter featuring the most important stories of the day delivered to your inbox every evening at 5pm.